The velocity ratio of a pullery systerm is 2 ,if the efficiency is 75% what is mechanical advantage? If the load is 120N what work is done by the effort if the load is lifted 0.5m?How much energy is wasted?

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

Both speed and velocity measure how fast something is moving. however, since speed is not a it does not require a(n question 6 options: a) quantity , unit b) magnitude, unit c) scalar, direction d) vector, direction

How do you know how many valence electrons an atom has?